S/Z cabling machine for laying fibers around a grooved pull-reliever

ABSTRACT

A cabling machine for laying optofibers, cables or the like in an oscillating, wavy path around a smooth pull-reliever, or into grooves having an oscillating, wavy shape which are extruded around a pull-reliever, i.e., so-called S/Z-cabling. The machine includes a pull-reliever pulling-off device, a braking capstan, a fiber reeling-off device, and an S/Z-bench (6) for laying the fibers around the pull-reliever. When used with a grooved pull-reliever (2), a laying-on tube (11) of the S/Z bench (6) is connected to a transmission (14), and a sensor (17) is connected to the transmission and functions to detect rotation of the laying-on tube (11) caused by the oscillating waveshape of the grooves. The reeling-off device (1) and the braking capstan (3) are controlled to cause the pull-reliever (2) to rotate to perform a corrective function.

This is a divisional of application Ser. No. 07/690,294, filed Apr. 24,1991, now U.S. Pat. No. 5,259,180.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a cabling machine, more particularly tolaying optofibers, cables or the like in an oscillating wavy path arounda smooth pull-reliever, or down into grooves of oscillating waveshapethat have been extruded around a pull-reliever, as in so-calledS/Z-cabling.

2. Description of Related Art

Cabling machines for laying optofibers or the like in an oscillating,wavy path around a smooth pull-reliever are known to the art. Thesecabling machines include an S/Z-bench which includes a laying-on tube ordiscs which are oscillated backwards and forwards for the purpose oflaying the fibers on the pull-reliever. The fibers, which pass along thelaying-on tube to a laying-on head located on the forward end of saidtube, become wound to a greater or lesser extent around the laying-ontube during operation of the machine, which causes the fibers to besubjected to friction forces. These frictional forces will vary inaccordance with the rotational movement of the laying-on tube at thatparticular moment in time, and when the fibers are wound to a greatextent on the tube, the frictional forces can be so high as to damagethe fibers.

Also known to the art are cabling machines which are intended to layoptofibers or the like in grooves of oscillating waveform extrudedaround a pull-reliever. These machines also include an S/Z-benchprovided with a laying-on tube or discs over which the fibers pass to alaying-on head. The pull-reliever is pulled rectilinearly through thelaying-on tube and, because of the oscillating form of the grooves, thetube tends to rotate forwards and backwards as a result of the fibersbeing guided down into the grooves. This rotational movement or twistingof the laying-on tube will also cause fibers to be wound around the tubeand subjected to frictional forces that are liable to damage the fibers,similar to the former case.

Thus, the known cabling machines have the disadvantage of subjectingfibers to large frictional forces with subsequent risk of damage to thefibers. Furthermore, the known machines are intended for laying fibersin an oscillating waveform, i.e. S/Z-cabling, solely on one type ofpull-reliever, namely either on a smooth pull-reliever or on apull-reliever on which grooves have been pre-extruded.

OBJECTS AND SUMMARY OF THE INVENTION

The object of the present invention is to provide a cabling machinewhich will not subject the fibers to harmful frictional forces and whichcan also be readily switched between modes in which fibers can be laidon both smooth and grooved pull-relievers. The above objects as well asother objects not specifically enumerated are accomplished by a cablingmachine in accordance with the present invention. A cabling machine ofthe present invention for laying a fiber in an oscillating waveformaround a smooth pull-reliever includes a pull-reliever reeling-offdevice, a braking capstan, a fiber reeling-off device, an S/Z-bench forlaying the fiber around the pull-reliever, a yarn spinner for fixatingthe fiber on the pull-reliever, and a wheel capstan and a taking-updevice for forwardly pulling and taking-up the finished cable,respectively, said S/Z-bench including a laying-on tube provided with alaying-on head, wherein the fiber passes over the laying-on tube up toand through a hole in the laying-on head, where it is laid on thepull-reliever and fixated with yarn taken from said yarn spinner,wherein said S/Z-bench includes an aligning mechanism which grips andguides the pull-reliever, and a motor which drives the aligningmechanism in an oscillatory rotational movement through a transmission,wherein said laying-on tube is connected to said transmission such thatan oscillatory, rotational movement is imparted to said laying-on tubeby said transmission in a direction opposite to the rotational movementof said aligning mechanism, wherein a sensor is connected to saidtransmission and controls the rotational movement of said motor andtherewith the rotational movement of said laying-on tube and saidaligning mechanism and wherein rotational movement of said laying-ontube is limited such that the fiber will only be wound on said laying-ontube to a slight extent, so as to minimize the frictional forces actingon said tube.

The objects of the invention are also accomplished by a cabling machinefor laying a fiber into an oscillating, waveshape groove extruded arounda pull-reliever, which includes a pull-reliever reeling-off device, abraking capstan, a fiber reeling-off device, an S/Z-bench for laying thefiber around the pull-reliever, a yarn spinner for fixating the fiber onthe pull-reliever, and a wheel capstan and a taking-up device forforwardly pulling and taking-up the finished cable, respectively, saidS/Z bench including a laying-on tube provided with a laying-on head,wherein the fiber passes over said laying-on tube up to and through ahole in said laying-on head, where it is laid on the pull-reliever andfixated with yarn taken from said yarn spinner, wherein saidpull-reliever reeling-off device and said braking capstan are rotatablymounted, wherein said laying-on tube is freely rotatable and is guidedby the action of laying the fiber into the groove in the pull-reliever,wherein said laying-on tube and a sensor are connected to saidtransmission, and wherein said sensor functions to detect rotationcaused by the oscillating, waveshape of the groove in said laying-ontube and causes said reeling-off device and said braking capstan torotate and perform a correction function which counteracts excessiverotation or twisting of said laying-on tube, such that the groove in thepull-reliever in the vicinity of said laying-on head will extendsubstantially rectilinearly and such that the fiber will extendsubstantially parallel with said laying-on tube in the absence offriction thereagainst.

The inventive cabling machine has the advantage of being usable for bothtypes of pull-reliever and also of minimizing the risk of damage to thefibers, since the fibers pass over the laying-on tube in a frictionlessfashion. This enables the fibers to be laid at a high production rate.

Further objects of the inventive cabling machine and further advantagesafforded thereby will be evident from the following, detaileddescription, in which the invention is described in more detail withreference to a preferred exemplifying embodiment thereof and also withreference to the accompanying drawings.

BRIEF DISCLOSURE OF THE DRAWINGS

FIG. 1 is a schematic front view of a cabling machine of the invention.

FIG. 2 is a front view of an S/Z-bench of the cabling of FIG. 1.

FIG. 3 is a detailed view of a transmission of the S/Z-bench of FIG. 2.

DETAILED DESCRIPTION

FIG. 1 illustrates schematically the general construction of a cablingmachine. The illustrated machine includes a reeling-off device 1 forreeling-off a pull-reliever 2, a braking capstan 3, unreeling devices 4for reeling-off fibers 5 which are to be laid around the pull-reliever2, an S/Z-bench 6, a yarn spinner 7 which is located immediatelydownstream of the S/Z-bench and which functions to fix the fibers on thepull-reliever, optionally a banding machine 8 or banding the fiber-laidcable to a finished cable, a wheel capstan 9 for drawing the cableforwards, and a coiling device 10 for coiling-up the finished cable. Thereeling-off device 1 is provided with a basic braking arrangement, andthe braking capstan 3 is provided with sensors for determining andsetting the tension in the pull-reliever 2, this being necessary so asto obtain a sufficient fiber surplus which will enable thetemperature-cycling requirement to be fulfilled. Both the reeling-offdevice 1 and the braking capstan 3 are rotatably mounted, for reasonsmade apparent herebelow. The fiber reeling-off devices 4 are arranged ina common station and include, in a known manner, basic brakingarrangements, forwardly pulling devices and sensors for measuring andadjusting the tension in the fibers.

The S/Z-bench 6 will now be described in more detail with reference toFIG. 2. The S/Z-bench can be said to be the hub of the cabling machineand of the invention, and includes a fiber-laying-on tube 11 over whichthe fibers 5 pass from the reeling-off devices 4. The fibers 5 areguided to the S/Z-bench so as to be conducted concentrically over thelaying-on tube 11 and up to a laying-on head 12 mounted on the outer endof the tube, where the fibers are guided and conducted down onto thepull-reliever 2 drawn through the laying-on tube. The laying-on head maybe of any conventional kind and is only shown schematically in the FIG.and will not be described in detail. The S/Z-bench 6 also includes analigning mechanism 13, a transmission 14 capable of being driven by areversable stepping motor 15, and an absolute sensor 17 connected to thetransmission over gearing 16.

The transmission 14 is illustrated in more detail in FIG. 3. Thetransmission includes two toothed wheels 18 which are in mutual axialalignment and through which the pull-reliever 2 can pass. The aligningmechanism 13 can be non-rotatably connected to one toothed wheel bymeans of a key-joint or the like, and the laying-on tube 11 can benon-rotatably connected to the other toothed wheel. Two further toothedwheels 19 and 20 are mounted perpendicularly to and at differentdistances from the toothed wheels 18, of which further toothed wheelsthe tooth wheel 19 is connected to the motor 15 and the toothed wheel 20is connected to the absolute sensor 17, via the gearing 16. An endlesstoothed belt 21 runs in a continuous loop over the toothed wheels 18, 19and 20, the arrangement being such that when one toothed wheel 18rotates in one direction, the other toothed wheel 18 will rotate in theopposite direction.

In the illustrated embodiment, the gearing 16 comprises a smallertoothed wheel which is connected to the toothed wheel 20 and whichdrives a large toothed wheel connected to the sensor 17 via a toothedbelt, although it will be understood that other types of gearing can beused. The gearing is intended to prevent the absolute sensor 17 fromrotating more than one revolution.

When cabling smooth pull-relievers 2, the reeling-off device 1 and thebraking capstan 3 are both stationary, i.e. not rotatable. The aligningmechanism 13, which comprises a number of gripping wheels which griparound the pull-reliever 2 and guide the same through the aligningmechanism, is connected to the transmission 14. The stepping motor 15 isalso connected to the transmission 14 and drives the transmission, andconsequently also the aligning mechanism 13 and the pull-reliever 2, inan oscillating reciprocating rotary movement. This movement is regulatedby the absolute sensor 17 via a regulating and controlling device. Thefibers 5 will therefore be laid on the pull-reliever 2 in an oscillatingwaveform and are fixated with the aid of yarn taken from the yarnspinner 7 immediately downstream of the laying-on head 12. The yarnspinner 7 is preferably a double-yarn spinner with which the two yarnsare laid in mutually opposite directions, thus in both an S-directionand a Z-direction. Because the laying-on tube 11 does not rotate when inoperation, the fibers 5 will pass parallel through the tube, and hencethe frictional forces acting on the fibers will be minimal.

In accordance with an alternative embodiment, for cabling a smoothpull-reliever 2, the laying-on tube 11 may also be connected to thetransmission 14. Because of the configuration of the transmission, boththe aligning mechanism 13 and the laying-on tube 11 will, in this case,be imparted an oscillating, reciprocating rotary movement, although indifferent directions. Rotation is regulated by the absolute sensor 17also in this case. Because of these counterdirectional rotary movements,the total rotation of the aligning mechanism 13 may be smaller than inthe former case, while still laying the fibers in an oscillatingwaveform on the pull-reliever. Total rotation of the laying-on tube 11is equal to the total rotation of the aligning mechanism 13, therewithlimiting the extent to which fibers 5 become wound around the laying-ontube 11 and thus also limiting the frictional forces on the fibers.

Cabling of grooved pull-relievers 2 will now be described. In this case,the aligning mechanism 13 is removed, the stepping motor 15 isdisconnected, and the laying-on tube 11 is connected to the transmission14. In this case, the reeling-off device 1 and the braking capstan 3 canbe rotated to effect a correcting function. When the fibers 5 are laidinto the oscillating, wave grooves in the pull-reliever 2, the laying-ontube 11 will tend to rotate. This rotation is detected by the absolutesensor 17 connected to the transmission 14, which now causes thereeling-off device 1 and the braking capstan 3 to rotate in a remedialor correcting fashion in response to the set turning-limits of thelaying-on tube 11 such that the grooves in the pull-reliever 2 willextend substantially rectilinearly past the laying-on head 12. Thelaying-on tube 11 will thus only rotate or twist to a limited extent andconsequently fibers 5 will not be wound onto the tube or subjected tofrictional forces to any appreciable extent.

In all of the aforedescribed alternative embodiments, it must be ensuredthat the free length of the pull-reliever 2, i.e. the distance betweenthe braking capstan 3 and the wheel capstan 9, is sufficiently great toenable the pull-reliever to rotate about its longitudinal axis.

It will be understood that the invention is not restricted to theaforedescribed and illustrated embodiment, and that modifications can bemade within the scope of the accompanying Claims.

I claim:
 1. A cabling machine for laying optofibers, cables or otherelongate elements into oscillating, waveshape grooves extruded around apull-reliever to produce a finished article comprising a pull-relieverreeling-off device for reeling-off a pull-reliever in a first direction,a braking capstan located downstream of the pull-reliever reeling-offdevice in the first direction, a fiber reeling-off device locateddownstream of the braking capstan in the first direction for reeling-offfibers, an S/Z-bench located downstream of the fiber reeling-off devicein the first direction for laying the fibers around the pull-reliever, ayarn spinner located downstream of the S/Z bench in the first directionfor fixating the fibers on the pull-reliever, and a wheel capstan and ataking-up device located downstream of the spinner in the firstdirection for forwardly pulling and taking-up the finished articlerespectively, said S/Z bench including a laying-on tube provided with alaying-on head so that the fibers pass over the laying-on tube up to andthrough holes in the laying-on head, where the fibers are laid on thepull-reliever and fixated with yarn taken from the yarn spinner locatedimmediately downstream of the laying-on head, the pull-relieverreeling-off device and the braking capstan being rotatably mounted; thelaying-on tube being freely rotatable and being guided by way of thefibers being laid into the grooves in the pull-reliever; the laying-ontube being connected to a transmission; and a sensor connected to thetransmission for detecting rotation of the laying-on tube caused by theoscillating, waveshape of the grooves in the pull-reliever and forcausing the reeling-off device and the braking capstan to rotate andperform a correcting function which counteracts excessive rotation ortwisting of the laying-on tube such that the grooves in thepull-reliever in a vicinity of the laying-on head will extendsubstantially rectilinearly and such that the fibers will extendsubstantially parallel with the laying-on tube in the absence offriction thereagainst.
 2. A cabling machine according to claim 1,wherein the transmission includes two mutually coaxial first toothedwheels through which the pull-reliever passes, two mutually parallelsecond toothed wheels spaced from and axially perpendicular to the firsttoothed wheels, and a toothed belt which extends in a continuous looparound said first and second toothed wheels, and the laying-on tubebeing connected to one of said first toothed wheels.
 3. A cablingmachine according to claim 2, wherein the sensor is an absolute sensorand is connected to the transmission via gearing.
 4. A cabling machineaccording to claim 3, including a banding machine positioned upstream ofthe wheel capstan.
 5. A cabling machine according to claim 4, whereinthe yarn spinner is a double yarn spinner with which the two yarns arelaid in mutually opposite directions.
 6. A cabling machine according toclaim 5, wherein a free length of the pull-reliever between the brakingcapstan and the wheel capstan is sufficiently long to enable thepull-reliever to rotate about its longitudinal axis.